Do you have a link to the gun? Typically any good quality spray gun will work for activator. You may not be able to find the actual guns we mention on this forum, but I believe the Devilbiss GPI does exist in Europe. If I remember correctly, @AquaGraphix could probably help you out with that.

The best activator paint style gun is the Devilbiss GPI it is specifically made for activator and Jim here at K2 can hook you up. I now have a pot system like the Brain pot. They are expensive but less error and you use less activator.

When I find specific activator guns they usually don't show any specs. Only on Aliexpress they show, and the maximum operating pressure is 150psi, so even much more than the 30 psi I can get in Holland. So this should mean that a gun with a higher operating pressure can be adjusted to 10 psi by the wheel maybe?

"Maximum" pressure is not the same as normal operating pressure. Just like in your car. It may have a top speed of 160MPH, but you wouldn't drive it that fast normally. You want to use a low a pressure that will completely atomize the activator. Test it on a piece of cardboard or paper. It should only be spraying tiny droplets as a mist, not larger droplets of spatter. The GPi mentioned above is the best for activator because it can properly atomize it at about 8psi. Lower pressure means less waste as over spray and less distortion in the film from being blown around on the surface of the water. Anything under about 12-15psi would be adequate.

@MCdyna ALL guns are going to show around 30 PSI or 2 BAR...thats what the guns are designed for based on the paint manufacturers specifications...we adjust the guns down based on our needs...you will not find a spray gun designed to operate at the low pressures our needs require...so you will just have to buy one and test it...I recommend a GPi from @AquaGraphix because they are simply the best spray gun out there for what we use it for...you are going to be around 8 to 10 PSI...

As for Spray Pots?...My experience has been less than satisfactory...we did not use less activator and because we use so many different films per day? Changing out the activator was a chore...as with making adjustments in our activator formulas...now it sits in the corner gathering dust...it's fun to look at though...lol...